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How much light is correct?

Hi all,
Different CPers has different ways of describing good lighting levels for different CPs.
CPers are generally accurate on temperature and humidity ranges as a standard measurement are used. However when lighting level is concerned, description such as direct, indirect, bright, shaded….. and so on.

I believe at tropical equator e.g. Singapore, light intensity would be have been much higher than, say USA. It will be helpful if the experts on this forum can provide the light intensity in Lux units for CPs….. please comment.

Thanks
 
I agree with you. I wish we had a accurate way of measuring light that everybody can understand. But in reality there really is no widespread measurement that everybody uses. In my job I mostly use watts to measure light, but watts is not really very accurate. The same amount of watts produce different amounts of light when you change the voltage and the bulb type.
I think lux is the most widespread measurement of light. I have never used this system and I'm not sure how many people here that use it.
 
Sorry, i can't help, either, but i did have a few comments. The problem with measuring light is that all light is not created equal. Because it comes in a whole spectrum, total energy (as Ozzy mentioned) is a poor measure, even if efficiencies of different artificial lighting technologies were all the same. Lux is more useful, but again doesn't tell the whole story because plants are more sensitive to different wavelengths of light than our eyes are (which is what the lux measurement is based on), hence lux is subjective, weighted in favor of what the eye sees rather than what the plant "sees".

It's becoming apparent to me that in the case of things like VFTs, sarrs, and many sundews, it's almost impossible to give them too much light, as long as heat doesn't become a problem.

Just my thoughts. Don't mind me.
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As a new cp'er I've been trying to glean information from the Web as well as one nice book by Paul Temple called, simply, "Carnivorous Plants", to keep my small group of plants alive and well. Temple suggests that for many plants a strong southern exposure is adequate, so long as the plants are not exposed to direct sun, which can cause burns, especially with sundews. But I'm going to be converting a ten gallon aquarium to a terrarium and would be interested in knowing what kind of lights would be best to use with that. Are the small flourescent ones that are used for aquariums adequate, or is a special "grow light" required? If anyone has experience with this I'd be interested in hearing from you. So far I just have a mini greenhouse with five plants, but I have great plans . . .

cpwitch
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Hi CPWitch

Welcome to the forums.
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Glad to have you here.

I grow some CPs in tanks and some outdoors. The tank CPs are mostly the ones needing higher humidity. It is pretty simple to provide light for them. A shop light from a hardware store will work fine (and is relatively cheap). I started with a 10-gallon tank and let me warn you...you will rapidly outgrow it!
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It wasn't long after I set up my 10-gal. that I moved on to a 20...and...another and another. lol

I, and many others, use one 40-watt cool white fluorescent and one Gro-Lux light in a 2-tube fixture. I have both 24" and 48" depending on my tank size. This has worked well for me. Some people use Sun Sticks. And there are other ways of lighting but the shop light and tubes are fairly cheap. I have timers on all of them to provide the hours of light they need (mine are set to 14 hrs). Incandescent lighting isn't very good and also creates a lot of heat which can cause problems. Be wary of some so called "Plant lights" as not all of them are truly made for plants.

Your VFT does not HAVE to be in a terrarium. They will grow fine in a window sill or outdoors. Just keep them in a tray or saucer of water. But of course if you want to keep in a terrarium that's fine...just bear in mind they appreciate good air circulation which will help prevent rot and mold.

Cobras are generally considered as needing cool roots. Different people use different methods and some people have found its not a big issue at all. If you see your cobra having problems, that might be an issue to investigate.

I hope that helps and if not, just ask more questions!

Suzanne
 
I have done some researching on the web.
The following points were extracted from many articles, hopefully can provide basic lighting requirement for plant in general.
Illuminance is a measure of the amount of light incident at a point (expressed in footcandles or lux (metric). Luminance, expressed in footlamberts, is a measure of how much light is reflected from or passed through a surface. It is more representative of what a person sees and takes into account reflective characteristics of room surfaces.
LUX = lm/m2, the intensity of light which falls on a surface.
Sunlight Intensity on Earth's surface can reach 90000 lux, this can happen at noon on a clear Tropical summer day, especially at higher altitudes.
Blue and red light are most efficient in stimulating plant growth.
Red light (6000 to 7000 angstroms) mainly controls maturation, and flower and seed production; it is particularly important to flowering plants. Used alone, red light will make plants grow tall and spindly. Blue light (4000 to 5000 angstroms) chiefly controls leaf development; plants grown under blue light alone tend to be short and stocky, with thick stems, dark green leaves and few flowers.

Incandescent lights (the round bulbs normally used in the home) can supplement natural daylight for foliage plants with low light requirements, but they do not provide enough light to meet and needs of flowering plants. They give off a large amount of red light and infrared radiation, most of which becomes heat. This causes cooling problems and burning of leaves. Because the light source is concentrated in a small area, light distribution is likewise restricted to a small area.

Fluorescent lights have a higher light efficiency than incandescent lights. emitting two and a half times as much light per watt. Fluorescent tubes vary in red-blue output. A combination of cool white and warm white is recommended for use on house plants.

The intensity and duration of illumination required vary from plant to plant. Older, mature plants need less light than young, active ones; flowering plants have high light requirements 6000 to 10,000 lux, most foliage plants need from 1000 to 6000 lux; variegated and colored foliage plants need more; for root cuttings, 1000 to 2000 lux is sufficient; flowering bulbs need 500 to 1000 lux.

The million dollar question is: what lighting levels are good for CPs? May be we can start some measurement? Got to get hold of a LUX meter quick……..
 
Hey all, quick note.

I had two terrariums, on my 55 I had 4 48" tubes (2 shoplites, double tube) I ran a mixture of cool and soft white (I like the color combo, and have achieved good results with it) However I could not succeed in growing flytraps and sun light loving dews in there, by the time the light reached the bottom, there was too little. So I set up a 10 gallon, on that, I put 2 24" double tubes fixtures (total of four tubes), same cool and soft whtie setup. this overlapped the setup a little, but the plants loved it, until I put them outside, where they are better off.

Now, I broke down the 10 gallon, up-ended the canopy on the 55, and added the 2 24" fixtures... I can not possibly fit anymore lights in there for the canopy is just chock full, there is no room!

If you are going with flourescents, I just don't think you can put in to much. Flourescents will NEVER rival the sun in it's intensity, and as long as you don't get the plants to close (the bottom is about 3 feet from the lights) you should be fine.

My adelaes died when I put new bulbs in, and dissapeared for a while, now I have adelae babies popping up all over the place under this setup, I have a flytrap (as an experiement) sitting in there happy as a clam with my nepenthes, so it's a mixture of relatively tough and sensetive plants, and all are thriving.

I am not advocating a willy nilly approach, but I do think if you use your head with experimentation, your plants will survive it.

As I can, I am planning on experimenting with 5200K metal halide, and compact flourescent lighting, which is more efficient than NO.
 
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